Viral hemorrhagic fevers (VHFs) : Introduction

What Are Viral Haemorrhagic Fevers (VHFs)?

Key Facts:

• VHFs = severe illnesses caused by RNA viruses from 4 families:

  • Arenaviridae (e.g. Lassa)

  • Bunyaviridae (e.g. CCHF, Rift Valley)

  • Filoviridae (e.g. Ebola, Marburg)

  • Flaviviridae (e.g. Dengue, Yellow fever, KFD)

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• Zoonotic origin: spread from rodents, bats, mosquitoes, ticks

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• Main features:

  • High fever

  • ↑ vascular permeability → hypotension, shock

  • Bleeding diathesis (↑ bleeding risk)

  • Multi-organ dysfunction

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• Transmission:

  • Direct contact with infected animals, vectors, or bodily fluids

Epidemiology of Viral Haemorrhagic Fevers (VHFs)

🌐 Global Overview of Viral Haemorrhagic Fevers